A few months ago, I purchased a 2015 Chevy 2500HD 4x4 crew cab. It does NOT have a vacuum booster. I have a SMI Air Force One and moved it over from my 2013 Chevy Silverado 1500 4x4, calling SMI was the answer as they forwarded me a diagram to change the tubes around inside the box, and all is well and works fine. Super excellent customer service!!!!
Remember, the Chevy owners manual is incorrect on wiring the brake control in, they have an improper grounding procedure listed that will NOT work.
The transfer case procedure is more complicated now and requires disconnecting the battery positive cable. I added a battery "kill switch" that makes it easy to disconnect the battery from the driver's seat without ever opening the hood.
Just make sure you have your windows closed before you kill the battery and get yourself a few extra keys!!! We got five keys for our truck now. One gets left in the ignition and one for locking the driver's door once the battery is turned off.
Made a little procedure sheet and stuck it to the back of the visor so wife can follow it correctly every time. If you don't take the extra two minutes to go slowly and follow the sheet, you can have an issue with the transfer case!! Then you will need to start all over again.
So far, couple thousand miles of it being towed, and no issues. Just take your time disconnecting the transfer case!!
Good luck. And its a real nice truck the rest of the time!!
2010 American Coach Revolution 42w; carrying 2014 HD Electra Glide Limited and towing 2015 Chevy Silverado 2500HD.
Dirt's for racing and asphalt for getting there.
410 Sprint Car's rule!